Griffin exited last Sunday's 31-28 overtime win over Baltimore late in regulation following an awkward hit to this leg. He was eventually diagnosed with a sprained right knee and was limited in practice all week.

The decision to start Cousins apparently came after Griffin was re-examined by doctors on Saturday. Coach Mike Shanahan had said the doctor's evaluation would play a factor in who starts.

Griffin tweeted: "The decision was not my own... But I will be there for my team!!! In every way I possibly can".

The Redskins did not say whether Griffin will be active for the game, or whether veteran Rex Grossman, who has been an inactive third-string quarterback for every game this season, will serve as the primary backup to Cousins.

Griffin, tied with Tom Brady with an NFL-best 104.2 passer rating, has led the Redskins (7-6) to within one game of NFC East-leading New York. Though Washington's postseason chances may take a hit without him, Cousins looked very capable late in Sunday's victory.

After Griffin went down against the Ravens, the former Michigan State standout stepped in to complete both his passes for 26 yards, including an 11-yard scoring strike to Pierre Garcon with 29 seconds left in regulation. Cousins then converted the two-point conversion on a quarterback draw to tie the game.

"He's ice. Like they used to say about Larry Bird, he got ice water in his veins," receiver Joshua Morgan said. "That's the best thing you can say about Kirk."

Cousins also earned high praise from Shanahan and seems more than capable of carrying the load if need be.

"You're running the scout team the majority of the time, and you're expected to go in there and perform," Shanahan said. "So there's a lot of pressure on people. Some people can handle it; other people can't. But when you prepare yourself like he has, it didn't surprise me that he was flawless in what he did."

While Washington is seeking its first five-game winning streak since 2005, Cleveland (5-8) has put together three straight victories for the first time since a four-game run to close the 2009 season.

After beating Pittsburgh 20-14 and Oakland 20-17, the Browns posted their most lopsided victory since 2003 last Sunday, 30-7 over Kansas City.

"It's all kind of coming together," said 14-year veteran Phil Dawson, who made three field goals. "We're just doing all the little things right now. Guys are hungry to come back to work every day. There's some energy around here that I haven't felt. This is all good."

Trent Richardson was limited to 42 yards on 18 carries against the Chiefs but scored his eighth and ninth rushing touchdowns to tie Hall of Famer Jim Brown's franchise rookie record. The bruising back is tied for third in the league with 10 TDs from scrimmage.

"I don't want to override my boundaries with, 'We're the best team,' or say stuff like that, but we're putting something together here and it's going to be beautiful," said Richardson, who was taken No. 3 overall in this year's draft -- one spot after Griffin. "We haven't arrived yet, but we're just trying to win to get to the next level and be an elite team."

While the Browns likely prepared for both quarterbacks, they could also have their hands full with Alfred Morris. The rookie back is coming off his third consecutive 100-yard effort, rushing for 126 yards and a touchdown against the Ravens. His 1,228 yards on the ground rank fourth in the league.

Slowing down Garcon could also prove crucial. The Redskins are 6-1 when he's active and 4-0 when he has at least four catches. Garcon has hauled in 17 receptions for 275 yards over his last three games, scoring in each.

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Scouting Report

Redskins-Browns: What to watch

After watching film of both teams, Scouts Inc. breaks down key elements of the Week 15 Redskins-Browns matchup.

• Get Richardson his touches: The Cleveland offense is built around Trent Richardson. He is its leading rusher and receiver in 2012. The Redskins have been exploited most often through the air, having given up 27 TDs and an average of 290 yards per game. They also gave up 186 yards on the ground against the Ravens in Week 14. Look for Cleveland offensive coordinator Brad Childress to get rookie quarterback Brandon Weeden going with high-percentage passes and a good dose of Richardson between the tackles.

Head to Head Matchups (Since 2001)

Research Notes

Robert Griffin III has taken contact on 66 of his 104 rushes this season (excluding kneel downs). Only Cam Newton has been hit on more quarterback rushes this season (85).

One of Robert Griffin III's strong points this season has been accuracy. Only 13.7 percent of his passes have fallen incomplete due to an under- or overthrown pass, best in the NFL. Only two of Griffin's four interceptions have come on an off-target pass, one more than his backup Kirk Cousins.

Lowest Pct of Off-Target Passes - This Season

Pierre Garcon has played in 7 games this season, but the Redskins are 6-1 with him in the lineup...Washington's offense is more productive in passing as well as scoring..When Garcon is out of the lineup, the Redskins are just 1-5 this season.